Drill



Patented Elec. 2li, 18922.

Fri

i ripiega?? ,y lil le l. .ln la' inermi.

Application filed April 26, 1921. Serial No. 464,626.

To all fro/0m #may concern.'

Be it lriiown that ll, GEORGE lll. DUNS- woRrI-i, a citizen of the United States, re'

siding' at Houston, in the county of Harris and State of rllenas, have invented certain new and useful improvements in a Drill, of which the following is a speciilcation.

This invention relates to new and useful improvements in a drill.

Une object of the invention relates to an improved forni of drill which niay be used either in drilling by the cable-tool process or by the rotary process and when usedin connection with a rotary is also adapted tor use as an underreainer. f-

Another object is to provide a bit which can be readily. collapsed for withdrawal from the Well.

l/Vith the above and other objects in View this invention has particular relation to certain novel features ofconstruction, 4operation and arrangement 01E parts, an exainple of which is given in this speeiiicationand illustrated in the accompanying drawings, wh erein Figure 1 shows a vertical sectional view olf the device shown in ex ianded position iu drilling, and n I .Figure 2 shows the bit in collapsed po sition in the process ot' withdrawal Vfrom the well. Referring now inore particularly to the drawings, the nunieral 1 designates .the well casing which is gradually let down into the bore as drilling progresses. rl`he bit is formed with a barrel, preferably composed of the upper and lower sections 2 and which are screwed together. rllhe upper end o1 the section 2 is reduced and outwardly threaded and connected to the drill stein 4: by means of the collar 5. Threaded into the lower end of the barrel there is an anchor 6 which has a central spiralled slot extending vertically therethrough. Pivoted to opposite sides ot the anchor are the outwardly curved side reainers or cutters 8, 8, which have bearings in the anchor in which their pivoted ends are confined by ineans oi a sleeve 9 which is fitted over the anchor 6. lThese side reainers are pivoted to swing laterally relative to the anchor.

Clamped between the adjacent ends ott the barrel sections there is a disc-like guide 10 having a cent al spiralled slot 11 therethrough and the water ports 12, 12 on opposite sides ci the slot. il spiralled shank faces 18, 18 and 13 works through the slots 7 and 11. The upper end oil1 this shank has a detachablecollar 1dsecured thereon by a nut 15 `and its lower end is formed into head 16 which carries the bit l?. This bit inay be of any type, a lish tail bit being shown'. The head 16 has opposing downwardly flared bearing adjacent thein the projecting shoulders 19, 19 which work behind the side reaniers 8, 8. f I

Il/Vhen drilling by the rotary/process the bit rests on the bottoin oi' the'bore'and the weight o the barrel and drill stein holds the anchor 6 against the head 16and the reaniers are held expanded by the sloping faces 18 of the head and are rein'lorced,'during rotation by theshoulders 19. These side reaniers, in expanded position, project out underneath the casing and iforin an enlarged bore sulicient to receive said casing' which gradually descends as the bore is nitide. lll hen drilling by the cable process a cable is attached to the upper end oi"- the barrel instead of the steni 4l, and through it the drill is alternately elevated and dropped. When dropped the bit strikes the bottoni of the bore first, and with a rotary or twisting motion, and the barrel and anchor block then descend relative to the head and the side reainers are suddenly projected outwardly by striking the sloping' faces 18 and cut into the walls or' the bore, also with a rotary inotion, and gradually cut away said walls and enlarge the bore, thus under reaining the casing. Upon elevation or' the drill the bit reinains on the bottoni of the bore until the guide 10 strikes the collar 14 and lifts it from said bottoni, thefbit ineanwhile rotating to sweep the bottoni of the bore clear of cuttings.

When it is desired to withdraw the drill it is elevated through the stein l, or through the cable, used in lieu thereof. The barrel and anchor 6 will inove upwardly, relative to the shank 13 and the bit carried thereby, releasing the faces 18 ironi the side reainers 8 and permitting thern to swing inwardly. The guide 10 will then engage against the collar 1d and the shank and bit will be thereby carried along with the barrel and the entire drill may be thus withdrawn from the bore.

lll/hen the drill is to be used as an underreainer a cable Q0 is attached to the upper end of the shank 13. This cable extends up' to the ground surface and through it the head 16 is held up closely against the anchor 6 and the side reamers thus held expanded and the devicemay then be held suspended anywhere in the bore and in position to ream out andenlarge` the bore by the rotation thereof.

The anchor 6 has suitable water courses 2l, 2l therethrough, through which water is admitted to the side cutters to flush them and keep them freed `from the formation which may adhere thereto.

What I claim is l. A. drill including a barrel, ananehor in the lower end thereof, side cutters carried by said anchor, a spiralled shank operating through `a correspondingly shaped bearing in the anchor, and a bit carried by the lower end of said shank.

2. A drill includingr a barrel, an anchor carried by the lower end thereof and provided with a spiralled ,bearing therethrough, side cutters pivotally mounted on said anchor, a spiralled shank working through lsaid bearing and having aliniitedvertical moyement relative thereto, and a bit carried by the lower end of said shank.

3. A drill including a. barrel, an anchor carried by the lowerend thereof and provided with a spiralled bearing theretnrough, side cutters pivotally mounted on said anchor, a spiralled shank working through said bearing and having a limited vertical movement relative thereto, and abit carried by the lower end oi said shank, and means carried by the shank and adapted to engage against and expand said side cutters.

l. A drill inc luding a barrel having spiral shaped bearings therein, a spiralled shank working through said bearings and having a limited lengthwise movement relative to the barrel, expansible side cutters carried by the barreha bit carried by the lower end of the shank, and meanscarried by the shank and adapted to work between and hold said cutters expanded.

5. A drill including a barrel, expansible side cutters carried thereby, a bit having a` limited lengthwise movement relative to the barrel, means movable with the bit and adapted to wedge between, and expand, the

cutters, and means supporting'said bit and formed to impart a rotary movement thereto as it moves relative to the barrel.

ln testimony whereof l have signed my name to this specification in the presence of two subscribing witnesses.

Grenen w. DuNswonfri-i.-

i. itnesses E. V. Hnnowar, Jas. W. OLIVER. 

